Tough call. Have to go with Hermione though. She has youth and energy on her side. Charlie Daniels Vs. 12-year-old Asian girl in a fiddle battle
(I assume you mean Connie Souphanousinphone?) Charlie Daniels. A Belieber vs. a Tumblr SJW in a fight to the death.
The Pegasi. Not only can they fly, they're historically a race of warriors. Maud Pie vs. Big Macintosh in a hoof wrestling contest.
Trixie is a powerful Unicorn that doesn't hesitate to fight dirty, and Rockette is an Earth Pony that is not entirely used to her current body. I'm going to say Trixie. Pinkie Pie vs. Rainbow Dash in a cider drinking contest.
Pinkie Pie especially if she buys twenty of them like she did in Super Speedy Cider Squeezy 6000 Mare Do Well vs. Batman
Batman. Batman always wins. If Batman were to fight Tirek, Batman would win. If Batman were to fight Sombra, Batman would win. If Tirek were to fight Sombra, Batman would win. Batman wins, because he's THE GODDAMN BATMAN. Drunk guy vs. stoned guy in an obstacle course.
Whoever is watching. THAT is who REALLY wins!!! But, anyway my money's on the stoner. Cliff Burton Vs. Geezer Butler in a bass duel
Elsa, her power is magic based and can effect his life force even in full ice mode. Godzilla vs. Unicron